An image display system such as a liquid crystal display system includes a transmission device, a reception device, and an image display device. A clock may be transmitted through a signal line separate from a signal line through which data is transmitted from the transmission device to the reception device or data in which the clock is embedded may be transmitted from the transmission device to the reception device (see Non Patent Literatures 1 and 2). For the data in which the clock is embedded, a timing of transition from a first level to a second level is in each unit period and information of a predetermined number of bits is provided in the unit period starting from the timing of transition. Also, one of the first and second levels is a high level and the other is a low level.
The transmission device inputs an image signal or the like from an outside and transmits image data and training data to the reception device. The reception device performs clock training on the basis of the training data received from the transmission device, samples the image data transmitted from the transmission device at a timing indicated by a clock after training, and transmits an image signal obtained by the sampling to the image display device. The image display device displays an image on the basis of the image signal transmitted from the reception device.
In an image display system such as a liquid crystal display system, generally, the above-described transmission device or a device including the transmission device is referred to as a “timing controller” and the above-described reception device or a device including the reception device is referred to as a “driver.” Also, generally, a plurality of drivers are connected to one timing controller.
In a transmission/reception system including a transmission device and a reception device which transmit and receive such image data, an active period in which the image data is transmitted and received and a blank period in which no image data is transmitted or received are provided. The training data for the reception device to perform training is transmitted from the transmission device to the reception device during the blank period.
Also, in the transmission/reception system, a first signal line for transmitting the image data and the training data from the transmission device to the reception device and a second signal line for performing communication between the transmission device and the reception device are provided. Through the communication via the second signal line, the transmission device notifies the reception device of a gamma value, various types of control information, setting information for a register, and the like in the image display system, for example, such as a liquid crystal display system. The communication via the second signal line conforms to protocols of serial bus standards, for example, such as Inter-Integrated Circuit (I2C) and a Serial Peripheral Interface (SPI).